IIRC, the Lee Web-site has updated the list about which primers are Okay to make use of. They now seem to solitary out FEDERAL particularly: 223 Rem. They suggested CCI (more durable primers) for all hundreds used in any firearm that has a free floating firing pin since the AR https://federal-primers-21044050.suomiblog.com/federal-215-gold-medal-match-primers-an-overview-47586067